


King Boo's Ghastly Ghoulish Ghostly Grudge

by RisingSonic17



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses, Super Mario & Related Fandoms, Super Smash Brothers
Genre: Action/Adventure, Attempted Murder, Breaking the Fourth Wall, F/M, Gen, Ghosts, Halloween, Halloween Costumes, Humor, Mild Sexual Content, Paranormal, Parody, Possession, References to Canon, Scary, Sexual Humor, Supernatural Elements, Yuri is a sexual deviant
Language: English
Status: Completed
Published: 2020-11-01
Updated: 2020-11-01
Packaged: 2021-03-08 17:15:55
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 6,374
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27320329
Author URL: https://archiveofourown.org/users/RisingSonic17/pseuds/RisingSonic17
Summary: Luigi and Daisy go out to New Smash City to enjoy Halloween along with the students of Garreg Mach experience their first Halloween. However, things go horribly wrong when King Boo returns along with a new friend to help seek revenge on Luigi. Will Luigi be able to survive this Halloween night?
Relationships: My Unit | Byleth/Bernadetta von Varley, Princess Daisy/Luigi, Yuris Leclair | Yuri Leclerc/My Unit | Byleth/Claude von Riegan/Bernadetta von Varley
Kudos: 4





	King Boo's Ghastly Ghoulish Ghostly Grudge

It was that season once again. The spookiest time of the year, Halloween. The day when all the creatures of the night come out and wreak havoc amongst those on the surface. While this was a good day for monsters, this was also a fun day for humans. Mortals go out dressed in costumes, indulge in some delicious candy, or binge horror movies. Trick or treating was a tradition all mortals joined in on this holiday to get more candy. The fighters in the Smash Mansion especially loved Halloween, except for one particular person.

Luigi was known for being a scaredy cat. It was one of his most distinguishing traits. Luigi has always been a shy and anxious individual, both to his benefit and detriment. He was especially anxious during Halloween. Monsters roaming around haunting people? What's so exciting about that?! Luigi is well acquainted with monsters, specifically the paranormal. His many encounters with King Boo always made the plumber shudder. Yeah he's defeated him, but all the near death experiences still shake him up.

This year was going to be different for Luigi. This time, he would go out to New Smash City and go trick or treating with the rest of the smashers. Most of them are already in the city, but he won't be traveling to the city alone. His girlfriend, Princess Daisy would be traveling with him. It really put Luigi at ease to have Daisy alongside him.

Luigi is currently in his room getting his costume on. For this Halloween, he decided to dress in his casino attire when he used to work at a casino back in the Mushroom Kingdom. It was a black tuxedo with a green bowtie and a fire flower pin on his tuxedo. Luigi looks at himself at the mirror and smiles to himself. Suddenly, the Polterpup pops out of the mirror.

"AHHHH!" Luigi's screams and falls on his butt. Polterpup lands next to his owner. "Oww…" Luigi rubs his butt. "Polterpup! What have I told you about scaring me like that?!" He scolds.

"Arf!" Polterpup happily barks.

Luigi sighs and shakes his head. "Just don't do it again okay?" The plumber gets up from the ground.

There is a knock on Luigi's bedroom door. "Hey Luigi! It's Daisy! Are you ready to come out now?" She asks.

Luigi walks to the door and opens it. "I'm ready Daisy! How about yo-whaaaaaaaaaaaaaaa?!" The plumber's mouth opens agape and eyes widened at his girlfriend.

Daisy is wearing an orange and white lingerié-like leotard with ruffles around areas such as the collar, the sleeves, and the leg-holes, wrestling boots with white stockings and a white bustier with a picture of a daisy on both bosoms.

Daisy flexes her arms. "What do you think sweetie? I look pretty tough huh?" She asks with a grin on her face.

"I-I-I-I...You...Uhhh…" Was all what Luigi could mutter from his mouth. He had his eyes fixated on Daisy's costume. He could see all of her thighs exposed and chest on full display, hugged tightly by her costume. Luigi slaps himself in the face to snap himself out of his trance. "W-Wow Daisy. That's a really good costume. Did you make it yourself?"

Daisy giggles and enters inside of Luigi's room. As the brunette walked into the room, Luigi's jaw dropped once again when he saw Daisy's butt exposed with her leotard covering her private area.

Daisy looks at herself in the mood and starts flexing. "I actually had Peachy help me make this. I wanted to be that wrestler that I saw on the TV one time. She looked really cool." Daisy turns to Luigi and points herself with her thumb. "You can just call "Flower Power"." She winks.

"I-I-I see." Luigi stammered. "It's very…" He swallows hard. "Revealing…"

Daisy smirks. She could tell that Luigi was turned on. She wanted to relish this moment. "Do you like it Luigi?" Daisy slaps her own butt, making it jiggle. "Do you like how this leotard shows off my ass?" She teases.

Luigi started to sweat profusely. "Y-Yes…" He admits.

Daisy puts her hand on Luigi's head and pulls him closer to her. She lowers him down to her ass, having his face pressed up against her own ass. "Yeah. You like these buns of steel don't you Luigi? You wanna take a gamble with me?"

Luigi's heart started pounding faster and his breathing started getting quick. " _Oh dear sweet Star Spirits. If I'm losing my mind here, I'm not going to survive November."_ He says to himself. Luigi shakes his head and stands back up. "W-We should start heading out to the city don't you think?"

Daisy laughs. "Sorry about that Luigi." She lightly pinches Luigi's cheeks. "It's always cute to tease you. Yeah, let's get going. I promised Peach we'd meet up with her and Mario."

"Daisy, aren't you afraid that you might get attacked again? Maybe by Dracula?" Luigi asks worriedly.

Daisy's winces at Dracula's name. She remembers her encounter with the King of Vampires. Becoming his slave and killing Luigi. Had it not been for the Belmonts, Mario, and Peach, who knows what would've happened to her. She still wondered what purple eyed monster was about.

"Well...I'll be ready for it this time." The brunette says with uncertainty. "I'm not gonna let that ruin my Halloween with you. Neither should you. Let's just try and enjoy this day."

Luigi nods. "Okay. Let's go enjoy Halloween!" He cheers.

"Yeah!" Daisy pumps her fist in the air. "Come on Polterpup." She calls the ghost dog.

Polterpup happily barks and starts flying around Daisy and Luigi's legs. The couple laughs and starts heading out of the mansion.

* * *

**New Smash City**

New Smash City was bustling with smashers all around the streets of New Smash City. A lot of them had already piled up a lot of candy. The most interesting thing about today was that this was the first time that the students of Garreg Mach are experiencing Halloween. They never had such an event back in Fodlan, so this was going to be something new for them.

The Black Eagles were all together. Dorothea is dressed up as former Pokemon League champion Cynthia, Caspar is dressed up as Spider Man, and Petra is dressed up as Aqua. Ferdinand dressed as Galo Thymos and Linhardt was dressed up as Turles. Hubert is also with the Black Eagles dressed as a vampire. It was a little embarrassing for the Black Eagles since Ferdinand was completely shirtless flaunting his body. Everyone groans in annoyance and walks away from their classmate.

Hubert was the only one who stood by Ferdinand. He shakes his head. " _You utter buffoon."_

Ferdinand sees the Black Eagles leaving him. "Hey! Where are you going?! Don't run away! I am Ferdinand von Aegir!" The noble announces.

"Not on this day you're not!" Caspar yells.

On the Blue Lion side, Mercedes is dressed up as Sypha Belnades and Annette is dressed up as Nezuko Kamado. The group of Dimitri, Felix, Sylvain, and Ingrid were dressed as the Ninja Turtles. Dimitri is Leonardo, Sylvain is Donatello, Felix is Raphael, and Ingrid is Michelangelo, they also had their signature weapons. To finish the package, Dedue is standing beside Dimitri dressed up as Master Splinter.

"I gotta say. I was a little worried when Pit mentioned these weird Ninja Turtles guys, but this actually worked out better than I expected." Sylvain says.

Ingrid folds her arms and pouts. "I don't understand why you have to be dressed as the smart one according to Pit."

"Because I am the smart one." Sylvain grins as he points to himself proudly.

"That's a load of bullshit and you know it." Felix barks. "I want to know why I am not the one with the sword and the boar is. He knows nothing about swordsmanship." He complains.

"Well Pit informed us that the leader is a sword user, so I must be the one to carry a sword. Not like I have a reason to use it. This is supposed to be an event for fun." Dimitri says. He turns to his retainer. "Speaking of which, how do you like your costume Dedue?"

"Simple attire. Nothing crazy. It is quite alright, milord." Dedue answers.

Dimitri smiles. "I'm happy to hear that."

"So, are we gonna stand around all day or are we actually gonna get some candy?" Sylvain asks. "There's also some really hot looking ladies in some skin tight outfits I'm trying to see." The orange haired male grins as he rubbed his hand.

Ingrid and Felix both punch Sylvain in the back of his head in anger. "Idiot!" They both screamed.

Meanwhile with the Golden Deers, Ignatz is dressed up as a painter, Leonie is dressed up as Captain Jeralt, Raphael is dressed as a giant chicken leg, and Marianne is dressed as a butterfly. Claude, Hilda, and to the dismay of Lorenz are dressed up as Ed, Edd, and Eddy. Hilda being Ed, Lorenz being Edd, and Claude being Eddy.

Claude turns to his classmates. "Looking good in your costumes you guys. This is fun. I wonder why we ain't ever had something like this back in Fodlan. Pit told me that the guy I'm dressed as is a notorious scammer. Scammers and schemers are pretty much the same thing, so it works for me." He says.

"Ugh." Lorenz groans in disgust. He tugs on his baggy red shirt. "To be dressed in the clothes of a commoner. I feel so...dirty. What would the people Fodlan think if they saw dressed like this?" He churns.

Hilda rolls her eyes at Lorenz. "Ahh, quit complaining you big baby! This is only for a day! I've never dressed up in these kinds of clothes, they're comfy. They are a little too big for me though." Hilda reaches into the jacket pocket and finds buttered toast inside of it. She tilts her head. "What the heck is doing in there? Oh well." She shrugs. Hilda takes a bite of the buttered toasts.

"Claude! When are we going to start getting candy?!" Raphael whines.

Claude puts his hand up. "Soon my delicious and meaty friend. We first need to come up with a scheme to try and get as much candy as we can get. Unfortunately, Lysithea has her hand tied with something else. So I will have to come up with a new plan. Don't worry. I'll be sure we get the most candy out of everyone."

"Not unless we have anything to say about it." A snarky voice spoke.

Claude groans. He knew exactly whose voice it was. "Yuri." The Golden Deer leader turns to Yuri who had Balthus, Hapi, and Constance standing behind him.

Yuri is dressed up as Kermit the Frog, having a full body suit and mask with Yuri's face being inside of Kermit's mouth. Constance is dressed up as Power Girl, Balthus is dressed as a minotaur, and Hapi is dressed up as Raven from the Teen Titans.

Yuri raises his finger. "It's actually Kermit the Frog today Mr. Von Riegan and I would appreciate it if you would refer to me as that, thank you." Yuri corrected as he spoke in Kermit's voice. "Hehehe. Perfect impression wasn't it?"

Claude rolls his eyes. "You look absolutely stupid. Did Pit recommend that costume to you?"

"Actually, this was a recommendation from Bernadetta's little friend Futaba. Bernadetta actually made the costume for me herself. At first, I wasn't going to wear the stupid thing. Then she was going to cry and she did that puppy dog whine she usually does. I couldn't say no to her so I conceded." Yuri puts his hand on his head and shakes it.

Balthus laughs. "The boss is a big ol softy for little Bernie. Can't say no to the fiance."

"But enough with the explanations!" Constance speaks up. "We overheard your mission to have the most candy out of everyone here. Well that's just not going to happen! For I, Constance von Nuvelle, as the superheroine Power Girl, will be the one to drown in the most sugary of sweets with my charm and super powers!" She says in a pompous tone.

"Yeah. The candy will be ours Claudester. So it's best if you give up." Hapi says.

"No way! We're going to be the one drowning in candy! Not gonna let you basement dwellers outclass us! If its a battle you want, then its a battle you're gonna get!" Hilda declares.

Claude and Lorenz look at each other in surprise. "Well color me surprised. This is the first time I've ever seen you so determined about anything Hilda." Lorenz comments.

"Look. I don't like doing too much work, but I hate losing just as much. I'm especially not losing to these guys. If we can win a mock battle, then we can definitely beat these guys in a candy getting competition." Hilda says confidently.

Claude grins at his best friend. "If only you had this attitude more Hilda, we probably would have gotten more chores done back at the Monastery." He jokes. He turns to the Ashen Wolves. "Well, I guess we have ourselves a little competition. Whoever is able to rack up the most candy by the end of the night, wins. Considering we have the numbers game on our side, we'll cover more ground than you guys."

"If my team wins, then I get to sleep in bed with Byleth." Yuri grins.

Claude's eyes widened. "WHAT?!" He yells so loud that people passing by turned their attention to the Golden Deer leader.

"What's the matter Claude? Are you chicken?" Yuri teases with a smug grin.

"BAWK! BAWK! BAWK! BAWK! BAWK!" Balthus teases, flapping his arms like a chicken.

"Ohohohohoho!" Constance laughs. "Claude is so much of a chicken, he might lay an egg because he's so scared." She grins.

"Claudester is a cock." Hapi bluntly says.

"He also likes cock too." Yuri teases.

Claude grinds his teeth and groans. "Alright! That's enough! We're kicking your asses! You got a deal!" The brunette extends his hand.

Yuri shakes Claude's hand. "By the end of the night, I'm going to be Byleth's big spoon."

Hilda giggles. "You really wanna fuck the professor, don't you Claude?" She grins.

Claude turns to Hilda. "N-No!" He yells, his face turning completely red in embarrassment. "I-I just don't want Yuri being in the same bed as Byleth."

"You're just mad I know how to suck Byleth's dick and you don't." Yuri chuckles.

"Shut up!" Claude yells. "Man I hate being engaged with you!"

Yuri puckers his lips at Claude and winks at him. "Love you too darling. Actually I don't. I love Byleth and Bernadetta. You, I just tolerate."

Lorenz rolls his eyes. "That rat brings out the beast's true colors." He muttered.

"Hey, that's racist." Balthus says, pointing at Lorenz.

* * *

Luigi, Daisy, and Polterpup finally arrive in New Smash City. There was a little delay because Luigi had to go back into the mansion and get his flashlight. They saw a lot of the smashers all dressed up in their costumes either trick or treating or performing pranks on each other.

Luigi turns to Daisy. "So, where did Peach say we're supposed to go to meet up with her Mario?"

Daisy scratches her head. "Unfortunately, Peach wasn't very specific about her location. She just said "meet Mario and me in the city and find us"." The brunette shakes her head. "I don't know why that girl couldn't have just been more specific."

"Welp. I guess we better start looking then."

"Arf!" Polterpup barks.

Daisy looks around and sees Byleth and Beth standing by a light pole with Beth having a plastic bag filled with candy and Byleth seemingly having nothing in it. Beth is dressed as a vampire, but in a more sexualized way. She is wearing a black floral lace corset along with her black shorts, black lace leggings, and boots, she also took off her knee brace. She still had her dagger hanging off the belt of her shorts. She had on a black cape that was red on the inside along with a black choker with a black cross necklace. She had on black lace hand warmers to match her leggings. She also wore red lipstick with some of it hanging off the side of her lip to look like she drank blood.

Byleth's Halloween costume was a little more tamed. Actually, the male professor didn't dress up at all. He was still wearing his usual attire, but he was wearing a red Oni Noh Mask.

Daisy waves over to the Eisner Twins. "Yoooooooo! Byleth! Beth! What's up?" She yells.

Byleth and Beth look and see Daisy waving over to them. "Oh hey, it's Daisy. Maybe she can help us." Beth says to Byleth.

Byleth nods. "Yes. Let's ask her."

The Eisner Twins walk over to Luigi, Daisy, and Polterpup.

"Hiya guys! Nice costumes by the way." Luigi says.

"How's your first Halloween going by the way? Looks like you scored big time tonight Beth." Daisy notes.

Beth grins. "That's right. Byleth and I were just going house to house and everyone just kept dumping candy in my bag. I'm pretty loaded today." The female professor shows off her bag of candy.

Byleth opens his bag. "I got a rock." He states. "Anyways, we have a bit of a problem on our hands. Do you think you can help us?"

Luigi tilts his head. "What's wrong?"

"Our students went off candy hunting with their group, but Bernadetta wanted to stay close to Byleth because she was too scared. Pit had the "bright" idea to jumpscare Bernadetta and make her run off." Beth explains.

"I chokeslammed him." Byleth states.

"You can see the crater Pit is currently laying on." Beth points to a crater on the street that Pit was left unconscious in. Pit was dressed up as Perseus.

Luigi and Daisy shrugged. "Well deserved." They said.

"We asked Lysithea and Ashe to help look for her, but they haven't come back. Last I checked, they were in the cemetery." Beth informs.

"We can help you look for them. I know you already have a lot on your plate looking after your other students." Luigi says.

"Yeah! Leave it to us! We'll find your students!" Daisy exclaims.

Byleth bows to Luigi and Daisy. "Thank you so much. Your help is very appreciated. The cemetery is just right through the park." The blue haired male points over to the location. "I'm very worried for Bernadetta. She probably had a panic attack or something. Please, find her and my other students."

"Yeah. We can't have my stepsister and my baby boy Ashe out there alone. Lysithea is a "grown up", I'm sure she's fine." Beth shrugs.

"We're on it! Come on Luigi!" Daisy says and she runs off to the park with Polterpup flying behind her.

"D-Daisy! P-Polterpup! Wait for me! I have the flashlight!" Luigi yells, trailing behind his girlfriend.

Daisy, Polterpup, and Luigi run through the park. The deeper they went, the more dark everything became around them. They make it to the cemetery, the wind only being the sound accompanying them.

Luigi swallows as he looks around the scary scenery. He quickly turns on his flashlight. He sighs in relief. "Okay. Now that we have the flashlight on. We should start looking for Byleth and Beth's students."

"Bernadetta! Lysithea! Ashe! Are you here?!" Daisy yells as she looks around the area.

"Arf! Arf!" Polterpup barks loudly.

"Hey! We're over here!" The smashers hear Lysithea yells.

Luigi and Daisy look up at a hill and see Lysithea and Ashe standing under a tree waving at them. Luigi and Daisy run up the hill with Luigi using his flashlight to keep the way clear. They make it to the students. Lysithea was dressed up as a witch while Ashe was dressed up in knight's armor.

"Thank goodness we found you quickly. Byleth and Beth were looking for you and got worried when you didn't come back for awhile." Luigi says.

"Were you able to find Bernadetta?" Daisy asks.

Ashe nods. "Yes. She's sitting up on this tree." He points up.

Luigi and Daisy look up to see Bernadetta sitting on a tree branch holding on to the tree tightly, shaking in fear. Bernadetta is dressed up in a full body purple bear cub suit. "H-H-H-Help me! Keep the monsters away from me!" The introvert screams.

Lysithea groans as she rolls her eyes. "Bernadetta! There are no monsters here! Get down from there! Byleth is worried about you!"

"Yes. Byleth and Beth would be happy to see you safe. Now come down." Ashe says.

"B-But I'll fall!" Bernadetta holds on to the tree, shutting her eyes.

Daisy extends her arms out. "I'll catch you Bernadetta! You can trust me!" She says.

"It's gonna be okay. We promise Bernadetta. We'll reunite you with Byleth." Luigi says.

Bernadetta opens one of her eyes and sees Daisy with her arms out, getting ready to catch her. The introvert gulps. She closes her eyes and pushes herself off the tree. "I MADE A MISTAKE! I'M GONNA DIE!" she screams as she falls.

Daisy catches Bernadetta. Bernadetta still had her eyes shut and was screaming, unaware that she was now safe in the arms of the Sarasaland Princess.

"Bernadetta! Stop screaming!" Lysithea yells.

Bernadetta stops screaming and opens her eyes. She sees that she had been caught by Daisy. Daisy smiles at Bernadetta. "I told you I wasn't going to let you fall."

Bernadetta blushes. "I'm sorry I caused you so much trouble…" She frowns.

Luigi shakes his head. "It was no trouble at all Bernadetta. We're just happy you're safe." He smiles.

"Great. We can go back to the city, bring Bernadetta to Byleth, and continue you on with this Halloween. I'm missing out on getting candy!" Lysithea complains. She then tries to straighten herself up because she sounded like a whining child. "B-Because it's part of the holiday and not because I love to stuff my face with sweets. What do you think I am? Some sort of child? Hahaha…" She laughs nervously.

"Yes. I would like to be with my friends. Not everyday you can spend a whole day dedicated to just eating sweets." Ashe smiles.

"A-Are you sure there won't be any scary monsters around?" Bernadetta asks nervously.

"No worries Bernadetta. Luigi and I will protect you from any monsters." Daisy says.

Luigi nods. "Yeah. Don't worry. I have my flashlight with me. My flashlight is good enough to scare away any monster." The plumber smiles confidently.

What Luigi didn't notice was that an evil and dark ghost was floating above him, bearing an evil smile. The ghost was the returning King Boo. His purple eyes glowing and blue tongue sticking out. Daisy, Bernadetta, Lysithea, and Ashe's eyes widened in horror. Lysithea raises her hand. "L-L-L-L-L-Luig-g-g-g-gi." She uttered.

"There's...something very horrific standing behind you…" Ashe points to behind Luigi.

Luigi tilts his head in confusion. "What?"

"Hehehehehehe…" King Boo laughs. "How about you use that flashlight to try and scare me?" He grins.

Luigi's body stiffens at the sound of the voice. He slowly turns around and flashes his flashlight at King Boo. "AHHHHHHHHHH!" Luigi falls down on his butt and crawls back to the rest of the group, who were now huddled up together.

"It's been awhile Luigi! How have you been? Nice costume by the way."

"W-W-W-W-What are you doing here King Boo?!" Luigi points to the ghost.

"What am I doing here?" King Boo begins to laugh. "A ghost can't come up to the surface and enjoy Halloween. This is our holiday after all. Speaking of ghosts, I brought a little friend with me."

"BLAAAAAAAAAAAAARGH!" Suddenly, a sack-like shape ghost appeared from underground and jumpscares the smashers. The smashers screamed in horror. Bernadetta faints in Daisy's arms. The ghost had a pointy turf on top of his head, a large maw with blue lips, sharp white teeth, and multicolored tongue and eyes. He also had two arms with three claw-shaped fingers on his hands. The ghost cackles.

"This is King Boom Boo. He's a Boo from another dimension! It's nice to see that the Boo name carries on throughout dimensions. I brought him here to celebrate Halloween...AND YOUR FUNERAL LUIGI!" King Boo smiles widely.

"Funeral?!" Luigi screams.

"That's right! No more of that stuffing you in a painting shit! I am going to kill you Luigi! Actually murder you! I will bring your soul to hell with me! Where we will haunt you and torture you for the rest of your life!"

Luigi shakes his head. "I don't like the sound of any of that!"

"But before that…" King Boo turns to King Boom Boo. "Let us summon our minions and give the people of the Smash Realm a Halloween they'll never forget."

The King Boos float up into the air and let out a roar. Boos from both dimensions started coming out from under the graves in the cemetery and started floating around all over New Smash City. King Boo and King Boom Boo began to cackle evilly.

"I don't like Halloween anymore!" Lysithea screams.

"I don't like it either!" Ashe screams.

"Let's get the hell out of here!" Daisy screams.

Luigi quickly got up off the floor and began to scurry out of the cemetery. Daisy with Bernadetta in her arms, Lysithea, and Ashe quickly followed behind the plumber.

* * *

Back in New Smash City, Byleth and Beth look up in the sky to see a dark cloud with a bunch of Boos flying around the city. Sothis appears in front of the Eisner Twins. The Progenitor God is wearing black cat ears on her head. She looks up at the sky and sees all the Boos floating above the city.

"What in the blazes is going on around here? Where did all these ghosts come from?!" Sothis questions.

Beth taps on Byleth's shoulder. "Byleth. We've got a problem." The female professor points forward to the street.

Byleth turns and sees that his students were being attacked by the Boos. The Boos went inside Dorothea, Caspar, Petra, Linhardt, and Ferdinand's bodies. Those possessed by King Boom Boo's ghost, had their big yellow eyes and large sharp mouths. Hubert was left unpossessed by the Boos because he was unphased by them. It looked more like he would work with him. The Boos shrugged and just left Hubert alone.

The Blue Lions weren't as lucky either. Dimitri, Dedue, and Ingrid easily got possessed. Annette screamed and cowered in fear as the Boos circled around her and laughed at misery.

"Annette!" Felix screams. The swordsman rushes in to go rescue his orange haired companion, leaving his other orange haired companion to fend for himself.

Sylvain extends his hand to Felix. "Hey! Felix! You're seriously not gonna leave me here with these ghosts are you?! What about me?! I need help too!" He yells.

The Boos began to circle around Sylvain and attack. Sylvain covers his head to brace himself for the attack. The Boos managed to rip off the entirety of Sylvain's costumes, leaving him in nothing but his heart shaped white boxers. The Boos laughed at the orange haired male.

Sylvain looks at himself to see that he was still alive with not even a scratch or bruise on his body. He smirks. "Ha, that's it? I thought you were actually gonna hurt me. Guess I'm too horny and smart for you hurt. What are you do now you stupid ghosts?" He spoke in a pompous tone.

The Boos look at each other and one of them goes inside of Sylvain's body and possess him. Felix and Annette also get possessed. The Boos start to approach Mercedes. However, Mercedes kept a smile on her face.

"Awwww, you are all so adorable." Mercedes says. The Boos raise their eyebrow at the cleric and look to each other. "How can I be afraid of such cuties like you? If you'd like, I can give you all my candy if that would make you happy."

The Boos all shook their heads and stuck their tongues out at Mercedes in disgust. They fly away from the cleric, not even bothering with her.

The Golden Deers and the Ashen Wolves were the easiest to possess for the Boos. Claude tried to run away with Lorenz and Hilda stepping in to protect him, but they got possessed along with the Golden Deer leader.

"No! Everyone!" Byleth screams.

Some Boos charged at the Eisner Twins to attack them. Sothis uses her powers to completely destroy the Boos. "Well I can't enjoy a nap with all these ghosts terrorizing the city. We have to do something." The Progenitor God says.

"HELP!" A group of voices scream.

Byleth, Beth, and Sothis turn to see Luigi, Daisy with Bernadetta in her arms, Lysithea, and Ashe running towards them. The Eisner Twins look up to see King Boo and King Boom Boo floating up in the sky behind him.

"Where are you going Luigi?! It's not a Halloween party without heads on a silver platter!" King Boo says. King Boo summons a spike ball and throws it at the smashers. The smashers jumped and screamed in horror as the spike ball just barely misses them and destroys a car.

"You guys! What's going on?!" Beth asks.

"King Boo! Arch-nemesis! Want to kill me this time! Boo from another dimension! Madness! Horror! Ahhhhhhhhhhh!" Luigi screams, putting his hands on his cheek.

"We managed to find Bernadetta. She's alright, she just fainted from the fright." Daisy informs. She gives Bernadetta to Byleth.

Byleth looks down at his unconscious fiance. "Bernadetta…" He mutters worriedly. "Are you two alright?" Byleth asks Ashe and Lysithea.

The two students nod. "Yes! Now can we please run away before we become ghost food!" Lysithea freaks out.

"I know knights are supposed to be brave, but I've never read a story where they had to fight ghosts! I can't do this! I was never prepared for this!" Ashe yells.

Luigi kicks the ground. "Darn it! Why did I have to leave my Poltergeist at home?! I can't stop the Boos without them!"

King Boo and King Boom Boo float above the group. "What a nice little group we have here. Enjoy the remaining time that you have living. We already have a lot of your friends with us. Don't you just want to join them?"

The possessed Garreg Mach students and smashers started marching towards the group like mindless zombies. They all had evil and twisted smiles on their faces. The non possessed smashers slowly backed away from the Boos and their possessed friends.

Luigi then feels something vibrating in his pocket. He reaches in his pocket and takes his Virtual Boo. Everyone else looks at Luigi confused.

"Well the hell is that Luigi?" Daisy asks.

"T-The Virtual Boo. Professor made it for me to contact him. I'm gonna answer." Luigi puts the Virtual Boo on his face. "H-Hello?"

In the Virtual Boo, it shows Professor in his lab. "Ahhh, Luigi! Happy Halloween to you! I can see that you're in a bit of a pickle here."

"You think asshole?!" Daisy screams.

"I can hear Princess Daisy. Hello there."

"Professor , this is not the best time to talk. We are about to get eaten by two King Boos. King Boo doesn't want to stuff me in a painting anymore, he wants to kill me!" Luigi says.

"Hmmm. That does sound frightening. I've been watching everything unfold while you were running away. It was very funny to watch." Professor chuckles. "There is an easy solution for this. I've created a device that's at the very top of the mansion. However, it is missing a lightbulb. All you have to do is bring that lightbulb to the mansion, hook it to my machine, and boom! All the ghosts will be gone. They do hate the light after all."

Polterpup appears from the concrete floor with a lightbulb in his mouth. Luigi removes the Virtual Boo and sees Polterpup with the lightbulb. The plumber takes the lightbulb from his dog.

"Okay, so all we have to do is take this lightbulb back to the mansion…" Luigi gulps.

King Boom Boo summons two fireballs in his hands. He throws the fireballs at the smashers.

"Look out!" Byleth yells.

The smashers jump out of the way of the two fireballs. "Everyone! We gotta run back to the mansion! Quick, through the forest!" Luigi screams. The group turns around and starts running away from the Boos to the Forest of Harmony.

"Get them!" King Boo commanded his armies and temporary puppets. The Boos and possessed smashers started flying and running after the group.

Neither of the running smashers wanted to look back and look at what was chasing them. Obviously they knew what, but they did not want to see how badly it looked. King Boom Boo was hot on the group's trail. He started eating through all of the trees in the forest. King Boo is using his crown to make lightning come down from the sky.

The lightning hits a tree and creates a forest fire. The smashers covered their mouths as they started to cough. Byleth holds Bernadetta closer to his chest to try and prevent the smoke from getting into her. Their vision started getting blocked out by the smoke.

"This is no good! We have to get out of this forest quickly! This forest fire will kill us before the ghosts have a chance to!" Sothis says.

Luigi coughs. "We're almost there! We just have to keep going!" The plumber coughed again.

"My lungs are gonna collapse at this rate…" Lysithea says weakly.

"I don't know if I can make it…" Ashe says weakly.

Beth grabs onto Lysithea and Ashe's hands. "Come on you two! Don't die on me here! We can make it!" She coughs.

The smashers manage to make it out of the moment. They take a moment to stand still and catch their breath. Luigi looks up and sees a giant purple cube with 's face on the side of it. On the top of the cube is a giant hole.

Luigi points up to the roof. "Guys I found it! That's where the machine is! We can do it! We just have to keep going!" He encourages.

The smashers run to the mansion, but are suddenly stopped in their tracks by a large blue flame in front of them. The smashers screamed in horror. King Boom Boo was breathing fire in front of the smashers to stop them. The smashers turn around to King Boo and King Boom Boo floating down to them with their Boo army and the possessed smashers.

"Time for our dinner King Boom Boo!" King Boo swirls his tongue around.

King Boom Boo swirled his multicolored tongue around. He cackled evilly. The smashers were now stuck.

Byleth turns to Sothis. "Sothis, is there anything you can do?!" He asks the Progenitor God.

Sothis shakes her head. "I would have to risk hurting the students as well. You wouldn't want that. I'm not too well versed in dealing with possession."

Beth groans. "Great...Now we're fucked."

Lysithea and Ashe hide behind Beth and hold on to her leg. "HELP US!" They screamed.

Daisy started breathing rapidly. Her body started to shake. She couldn't think straight with how much closer the ghosts were inching closer to her. She internally cursed herself. She hated to admit it, but she was scared out of her mind. They could very well die here.

Luig felt his knees starting to wobble. Suddenly, an idea struck in his head. He turns to Daisy. "Daisy! I need you to chuck me!"

Daisy turns to Luigi. "What?!" She tilts her head in confusion.

"Throw me up to the roof! I can probably make it up there if you throw me far enough! I don't know! Maybe it will work!" Luigi freaks out.

Daisy groans. It wasn't like she had any better plans. However, she felt like throwing Luigi would be enough. She had to improvise. She sighs. "Sorry sweetie, this is gonna hurt." The brunette cracks her knuckles.

Daisy uppercuts Luigi and sends him flying so far up that he reaches up to the roof. Luigi lands on the roof next to 's machine. Luigi slowly stands up, holding onto his head and groaning in pain. He shakes it off and quickly puts the lightbulb inside of 's machine.

The lightbulb shined bright. King Boo and King Boom Boo began to wail. "Damn you Luigi! Damn youuuuuuuuuuuuuuuuuuu!" King Boo screamed as he burned with King Boom Boo. All the other Boos along with the Boos that were possessing the smashers and Garreg Mach students left their bodies and burned as well.

The possessed smashers all collapsed to the floor unconscious. The fire disappears around The Eisner Twins, Daisy, Sothis, Lysithea, Ashe, and Bernadetta. Luigi looked over the roof to see that all the Boos were gone and that everyone was safe. He sighs in relief.

"Sweetie you did it!" Daisy cheered.

"You really saved our butts Luigi! Great job!" Beth smiles.

"Yeah Luigi!" Lysithea and Ashe cheered.

Bernadetta slowly opened her eyes. She looks up at Byleth. "B-Byleth…" She spoke weakly. "W-What happened? Where am I?" She asks.

Byleth looks down and smiles at Bernadetta. "It's alright Bernadetta. You just had a nightmare. It's over now." He says.

Bernadetta hugs Byleth. "Don't leave me tonight…"

"I promise I won't." Byleth cooed as he rubbed Bernadetta's back.

"At least everybody is safe, we should inform Master Hand and Crazy Hand about this. They can help us heal everyone." Sothis says.

"Hey!" Luigi yells as he waved to the smashers. "Next Halloween, I'm staying home! I'm never going out ever again! This was the worst Halloween ever!" He complains.

Luigi sighed in relief. He was happy that everyone made it out alive. He just wished that he could have one normal Halloween without almost dying. I guess that was too much to asks for one plumber.

**Author's Note:**

> The costumes chosen for Dorothea, Petra, Caspar, Linhardt, Ferdinand, Annette, Mercedes, and Sylvain were chosen because their voice actors did the voice for the characters the Three Houses characters are playing as. The Aqua Petra is dressed as is from the anime Konosuba. Yuri is Kermit the Frog because Kaggy plays as Kermit for his youtube channel and for the youtube channel Devilartemis. Beth's outfit was inspired by a Twitter comic by artist Hikaru_No_Hana. Check them out, they make really good Dimitri x Female Byleth stuff. For those who don't know, King Boom Boo is the boss from Sonic Adventure 2. Freaky thing that boss is. The ending of the fic was inspired by the Mario Party 1 minigame "Running of the Bulb", and the machine that built was supposed to look like a Gamecube.
> 
> Happy Halloween folks. Hope you all enjoyed the story. Kudos if you liked, reviews are always appreciated. I always love to hear what you have to say.


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